The plain grey ones, like in the picture, are named Marauder's Boots. They are fully moddable medium armor. There is also a red and black set (also medium and moddable) called Resilient Lacqerous Boots.

Proboly the only boots you can find that are medium armor and look like armor, the rest are boots that barely go above the ankles (and look like armored socks on body types 3 and 4).